Lubricating composition



Patented Sept. 27, 1949 LUBRICATING COMPOSITION Paul W. Fischer, Long Beach, Calil'., assignor to Union Oil Company of California, Los Angeles, Calif., a corporation of California No Drawing. Application May 30, 1945, Serial No. 596,803

This invention relates to lubricating oil addition agents designed to improve the lubricating properties of lubricating oils for use under conditions of severe service such as those encountered in Diesel engines, and the like,and to lubricating oils containing these addition agents.

The primary object of this invention is to procants are effective only within certain limits of engine operating conditions and when these limits are exceeded deterioration of the lubricating oils results causing undesirable ring sticking, bearing corrosion, sludge formation, piston lacquering, and the like. Addition agents have been developed and used in lubricating oils to minimize this deterioration and to reduce its deleterious 1 effects if it does occur.

Addition agents which have been proposed for the improvement of lubricating properties of lubricating oils are many in number. In general these agents are designed to function in some specific manner; for example, an additioiragent to which is attributed detergent properties is one which tends to keep pistons, rings and valves free of lacquer and varnish-like deposits. Oil-soluble metal salts of sulfonic acids are perhaps the most 7 used addition agents to improve the detergent properties of a lubricating oil and their use is well known in the art. Prevention of bearing corro sion is another specific function for which lubricating oil addition agents have been designed. Addition agents which perform this function include phenolic compounds, metal salts of the reaction products of a sulfide of phosphorus and an alcohol, metal salts of the reaction products of a sulfide of phosphorus and metal sulfonates such 25 Claims. (Cl. 25232.7)

as those disclosed in U. S. Patent 2,350,959 to Cook et al., and many others.

This invention resides in lubricating oils, preferably mineral lubricating oils, containing 01- soluble metal salts of the reaction products of phosphorus pentasulfide, or other sulfides of phosphorus, or even oxides of phosphorus such as phosphorus pentoxide and phosphorus trioxide with a sulfonic acid.

I have discovered that the performance of internal combustion engines under severe service conditions such as those encountered in Diesel engines can be markedly improved by the'use of a lubricating oil, preferably a mineral lubricating oil, to which has been added small amounts of an oil-soluble metal salt of the reaction product of a sulfide or oxide of phosphorus and a sulfonic acid.

I have discovered also that the lubricatin properties of a lubricating oil can be markedly improved by the addition of these same small amounts of an oil-soluble metal salt of the reaction product of a sulfide or oxide of phosphorus and a sulfonic acid together with small quantities of other lubricating oil addition agents. Such other addition agents which maybe used in conjunction with the oil soluble metal salt of the reaction product of a phosphorus sulfide or, oxide and a sulfonic acid include oil-soluble metal sulfonates; oil-soluble metal salts of phenols and particularly alkyl or cycloalkyl, substituted phenols such as those having more than about 12 carbon atoms per molecule; oil-soluble metal salts of phenol sulfides or alkyl or cycloalkyl substituted phenol sulfides and particularly those having alkyl substituents containing at least about 4 carbon atoms; oil-soluble metal salts of fatty acids, halogenated fatty acids or substituted fatty acids such as dichlorostearic acid, phenyl stearic acid and the like; oil-soluble metal salts or soaps of rosin acids such as abietic acid, hydrogenated rosin acids and the like; oil-soluble metal salts or soaps of acids produced by oxidizing high molecular weight hydrocarbons or hydrocarbon fractions such as parafiin wax, paraflinic lubricating oil fractions and the like; oil-soluble metal salts of the reaction products formed by reacting a sulfide or oxide "of phosphorus with an alcohol or 3 with a phenol; oil-soluble metal salts of phosphonic or phosphinic acids obtained by reacting elemental phosphorus with hydrocarbons as described in U. S. Patent No. 2,311,305 to Ritchey ties of a lubricating oil, but that any of these indicated combinations may be used in conjunction with a third lubricating oil addition agent which may be any one of those described as the second component of my combination addition agent to impart specific desirable properties to lubricating oils.

The oil-soluble metal salt of the reaction product of a sulfideor oxide of phosphorus and a sulfonic acid to be used in the practice of my invention may be prepared by first reacting a sulfide or oxide of phosphorus with a sulfonic acid and then forming a metal salt of the reaction product. Thus a phosphorus sulfide or oxide and preferably a sulfide in amounts in the order of from about 3% to 50% and preferably from about 10% to by weight of the sulfonic acid used, is reacted with a sulfonic acid, preferably a petroleum sulfonic acid, for one to twelve hours at temperatures of about 100 F. to 400 F., preferably between about 150 F. and 250 F.;'200 F. being a particularly desirable temperature. Sometimes it is desirable to employ a solvent or thinner to reduce the viscosity of the sulfonic acids during the treatment with phosphorus oxide or sulfide in order to facilitate mixing, temperature control and the like. Solvents such as naphtha or low boiling gasoline fractions are highly desirable for this use. The reaction when carried out with a sulfide of phosphorus, proceeds with the evolution of hydrogen sulfide and is generally continued until such evolution ceases. When phosphorus pentoxide is employed water is one of the reaction products. Moreover it has been observed that when the reaction'is effected with phosphorus pentasulfide elemental sulfur is .one of the reaction products.

The reaction product is acidic and capable of forming salts with basically reacting compounds. Salts may be prepared directly from the crude reaction product or the reaction mixture may first be blown with nitrogen, fuel gas or other inert gas or with steam to remove volatile reaction products from the mass. The desired. oilsoluble' metal salt is usually prepared by neutralization of .the above reaction mixture, directly or following the blowing with inert gas, with a basic compound of the desired metal such as the oxide, hydroxide, or carbonate, or it may be prepared by first neutralizing the reaction mixture with a hydroxide, oxide oi carbonate of an alkali metal, such assodium, potassium or lithium and then preparing the desired metal salt from the alkali metal salt by metathesis. For example, a heavy metal salt, such as the nickel salt, may be prepared by metathesizing the sodium salt of the reaction product with a nickel salt, such as nickel chloride or nickel sulfate, using conditions well known in the art for efi'ecting reactions of this type. When direct neutralization of the reaction mixture with a metal hydroxide, oxide or carbonate is carried out it is sometimes advantageous to dilute the reaction mixture with about an equal volume of a lower boiling hydrocarbon or hydrocarbon fraction such as a low boiling 4 gasoline or naphtha fraction or the like, and to use a small amount of water along with the basic metal compound. Under such conditions and particularly if slightly elevated temperatures are employed,'the neutralization proceeds to completion in a rather short period of time.

Phosphorus compounds which may be employed include phosphorus pentasulfide, phosphorus trisulfide, phosphorus pentoxide and phosphorus trioxide as well as mixtures of these sulfides and/or oxides.- Also in place of a sulfide or oxide of phosphorus I may react sulfonic acids directly with phosphorus and sulfur. In the following description the term."phosphosulfurizatiom will be employed to indicate the reaction of a phosphorus sulfide or oxide or of phosphorus and sulfur with a sulfonic acid.

Many types of sulfonic acids are suitable for use in the practice of my invention. The oil-soluble petroleum sulfonic acids commonly known as mahogany acids are the more desirable acids and in general I prefer to use those sulfonic acids having a molecular weight in the range Of about 300 to about 500 or higher. These sulfonic acids may be prepared by direct sulfonation of a suitable petroleum fraction with a sulfonating agent such as fuming sulfuric acid, gaseous sulfur trioxide, chlorosulfonic acid, and the like, to form oil-soluble sulfonic acids which can then be treated ac cording to the method of my invention. Petroleum sulfonic acids may also be prepared from oil-soluble sodium salts of petroleum sulfonic acids obtainable on the market under various trade names. For example, Petronate, sold by Sonneborn Sons Inc. of New York city, contains about 40% by weight of mineral oil and 60% by weight of oil-soluble sodium salts of petroleum sulfonic acids. The acids may be prepared from these salts in any of several ways well known in 'the art for converting sodium sulfonates to sulfonic acids, such as by treatment of the salts with a 60% by weight solution of sulfuric acid, treatment of the salts with a suitable ion-exchange resin, treatment of the salts with gaseous hydrogen chloride in an anhydrous medium, etc.

Although many hydrocarbons and hydrocarbon fractions may be used in the preparation of sulfonic acids by treatment with sulfonating agents, there appear to be great differences in their reactivity, i. e., in the ability of the various hydrocarbons or hydrocarbon fractions to form the desired sulfonic acids. Thus, although petroleum distillates boiling in the lubricating oil range may generally be employed as the sulfonation stock, the yields of the desired acidic products are usually low and the products are contaminated with undesirable oxidized, polymerized or too highly sulfonated bodies which are objectionable and which are difilcultly separable from the desired reaction products.

I have found that by various means described undissolved. By controling the amounts ofisol-x vent and other conditions of extraction such as temperature it is possible to control the proportion of any given stock which will be dissolved.-

Moreover, by the use of two extraction steps it is possible to separate the original lubricating oil fraction into three fractions, i. e., a first extract, a second extract and a final raflinate. In this case the first extract would comprise the most highly aromatic molecules, the final railinate would comprise the most highly parafilnic molecules and thesecond extract would comprise molecules which are more aromatic than the molecules-present in the raflinate but less aromatic and thus more paraflinic than the molecules present in the first extract. Such a material, i. e., the second extract, would constitute a desirable sulfonation stock. Such a fraction may be obtainedfrom substantially any lubrieating oil stock whether obtained from naphthene or paraflin type crude oil, but the amount of .the desired fraction obtainable will vary with the type of stock employed and with the efliciency of the solvent fractionation used to produce it. Although the physical characteristics of the desired intermediate fraction will vary with the type of crude oil from which it has been produced and with the viscosity of the fraction extracted, in general, the viscosity gravity constant (VGC) should be within the limits of about 0.82 and about 0.90 and preferably within the limits of 0.84 and 0.88. Viscosity gravity constant is a relationship between the viscosity and gravity of an oil and is described by Hill and Coates in the Journal of Industrial and Engineering Chemistry, vol. (1928), page 641. The limits indicated are not the'limits for the average VGC of the fraction but rather they represent the mac-.- tical limits of the VGCs of the molecules present in the desired fraction. Under any circumstance the desirable fraction will not contain more than about 20% by volume of material having VGCs outside of the range of 0.82 to 0.90 and preferabl 0.84 to 0.88. The presence of undesirable material in a fraction selected for sulfonation may be determined by a solvent fractionation involving two or more solvent extractions. Thus, extraction of the particular fraction under conditions such that 5% to 10% of the fraction will be removed as extract shouldproduce an extract oil having a VGC not greater than about 0.90 and preferably not greater than about 0.88. Furthermore, extraction with a solvent which will dissolve to of the fraction should leave 5% to 10% of a raffinate oil having a VGC not less than about 0.82 and preferably not less than 0.84.

In preparing a particularly desirable sulfonating stock, a lubricating oil fraction of a waxy Santa Fe Springs (California) crude oil was prepared by vacuum distillation in the presence of superheated steam. This distillate was dewaxed by diluting with 4 volumes of liquid propane, cooling to -50 F. and filtering to remove the wax. The propane was then removed by a topping distillation. The results of tests on the waxy distillate and on the dewaxed distillate were as follows:

Waxy Dis- Dewaxed tillate Distillate 2600 5438 799 1400 108. 5 139.2 30 -10 y ii 0. 876 0.887 int, F -1-.. 15 Flash point, Cleveland open cup, F 495 505 amounted to about 45% by volume, of the dewaxed distillate. The phenal extract was further treated with 7 volumes of furfural at 150 F. to produce, after removal of the furfural, a iurfural raflinate and furfural extract. The furfural raffinate amounted to about 35% by volume of the phenol extract or about 19% by volume of the dewaxed distillate. This furfural raffinate is a particularly desirable hydrocarbon fraction for reacting with a sulfonating agent tto produce sulfonic acids for use in my invenion.

The characteristics of this furfural raflinate fraction are given below together with the characteristics of the phenol raifinate, phenol extract and furfural extract.

Furgg f Phenol i'ural Furfiiral Hate Extract Raffi- Extract nate Gravity, API 28. 7 Viscosity, SUB at 19 7 100: F... 729 110,000 38.00 1 1, 400,000 F. 305 12, 354 87, 197 210 73. l 394 131 919 Conradt sari1 carbon, per

oe n resi ue 0. 03 2. 0 l. Iodine No. (Hanus) mg. 4 5 8 Iodine absorbed per g... 0. 62 3. 1 l. 2 24. 4 Sulfur, per cent l. 04 0. 97 1.05 Carbon, per cent 86. 00 87. 57 85. 40 86. 82 Hydrogen per cent 14. ll 10. 87 12. 33 9. 93 Viscosity index 90 -270 28. 9 820 Viscosity gravity constant based on viscosity at 210 F 0. 806 0.864

l Extrapolated.

The preferred hydrocarbon fraction to be used in the practice of my invention may also be prephenol extract in phenol or the original phenol extract phase may be cooled untilthe desired raflinate has separated or a suiileient quantity of water may be added to the extract phase to release or reject the desired proportion of raflinate. Also a lower boiling hydrocarbon, such as propane, butane, a light gasoline or naphtha fraction, or the like, may be added to the phenol extract phase to eifect the separation of the desired raiiinate. Combinations of these treat-' ments may be used as would be understood by one skilled in the art. I

It is also possible to produce the same desirable material by using other selective solvents at any or all stages of the process as outlined above in place of phenol and furfural. Thus the first extraction may be carried out with phenol, furfural, sulfur dioxide, sulfurdioxide-benzene, nitrobenzene, or some other suitable solvent and the second extraction carried out with the same solvent under different conditions of temperature, solvent ratio, etc., or with a difierent solvent suitable for effecting the separation of the desired material.

Among other methods of preparing the desired material which will be obvious to those skilled in the art, may be mentioned that of changing the solvent and/or conditions of extraction in such a manner that the desired material will be found in the first raflinate fraction rather than the extract fraction.- A second extraction may then be performed on the rafiinate from the first extraction usingany suitable solvent and adjusting conditions of extraction, temperature, solvent ratio, etc., in such a manner that the desired hydrocarbon fraction will be obtained as a second extract from the first raflinate.

Sulfonic acids are usually prepared by dissolving a. weighed amount of the hydrocarbon fraction described above as furfural rafflnate in about an equal volume of a lower boiling hydrocarbon solvent, such as a gasoline or naphtha fraction boiling in the range of 200 F. to 300 F., and treating the solution with 60% fuming sulfuric acid. The sulfuric acid is added slowly and means of cooling is provided so that the temperature of the reaction mixture is maintained below about 75 F. The total amount of fuming acid employed is generally about two-thirds of the weight of the hydrocarbon fraction being sulfonated although this may be varied depending upon the characteristics of the sulfonation stock. After the fuming acid has been added and thoroughly mixed with the naphtha solution of hydrocarbonfraction the reaction mixture is allowed to stand for some time, for example to 16 hours, during which time the hydrocarbon layer, which contains the oil-soluble or .mahogany sulfonic acids, separates from the aqueous sulfuric acid layer, which contains the water-soluble or green sulfonic acids. The two layers are then separated as for example by decantation and the hydrocarbon layer treated with a sulfide or oxide of phosphorus in the manner described hereinabove. Although the mahogany acids, described hereabove, are the preferred sulfonic acids to be treated with a sulfide or oxide of phosphorus according to the process of my invention, it is known that relatively large proportions of green acids, described hereabove,

may be solubilized in hydrocarbon solutions by the oil-soluble mahogany acids and such mixtures of mahogany sulfonic acids and green sulfonic acids, the latter solubilized by the mahogany sulfonic acids, may be employed in the preparation of my new lubricating oil addition agents.

The phosphosulfurization product or the product obtained by reacting a sulfonic acid with a phosphorus compound such as a phosphorus sulfide .or phosphorus oxide will be referred to 'the desired proportions of reaction products as determined by their phosphorus content. When these reaction products are employed as the only additive agents in the preparation of a lubricating oil the final oil will desirably contain between about 0.01% and about 0.5% by weight of phosphorus and preferably between about 0.05% and about 0.2 by weight of phosphorus.

In preparing lubricating oils containing the reaction product of a phosphorus sulfied or oxide with a sulfonic acid together with other addition agents such as sulfonates, phenates and the like, the proportion of reaction product should be such that the phosphorus content due to the presence of said reaction product wil also be in the order of from about 0.01% to about 0.5% and preferably in the range of about 0.05 to about 0.2% and the second additive, i. e., sulfonate, phenate, etc., will constitute between about 0.1% and about 5.0% by weight and preferably between about 0.5% and 2.5% by weight of the finished oil. 7

The determination of the percentage of phosphorus in the concentrates and in the finished oils has been carried out by a standard analytical procedure. The phosphorus, in a weighed quantity of the material to be analyzed, is first converted into the phosphate form by oxidation with' Analysis, page 676 (1936) for the determination of phosphorus in steel. In this method of analysis the phosphorus is weighed as magnesium pyrophosphate.

Oil-soluble metal sulfonates which may be used in conjunction with my reaction product as a second addition agent include the oil-soluble metal salts of substantially any sulfonic acid. Thus any of the sulfonic acids described herein above as phosphosulfurization stocks may be converted into an oil-soluble metal salt and employed as the second additive. The preferred sulfonic acids, however, are those obtained by sulfonating an intermediately refined pertoleum fraction in the lubricating oil range such as the furfural reflinate fraction described hereinabove.

Oil-soluble metal salts of phenols which may be used in the practice of my invention include the oil-soluble metal salts of many phenolic materials such as those of alkyl or cycloalkyl substituted phenols having more than about 12 carbon atoms per molecule as well as phenol sulfides of the alkyl hydroxy phenyl thio ether type. Thus metal phenates such as those described in U. S. Patent 2,281,401 to Wilson and U. S. Patent 2,344,- 988 to Kavanagh et al. may be employed. Phenol sulfides of the above type which may be employed are described in U. S. Patent 2,139,766 to Mikeska et al. and similar compounds together with their method of preparation are described in U. S. Patent 2,139,321 to Mikeska et al.

Suitable oil-soluble metal salts of synthetic organic acids produced by oxidizing hydrocarbons or hydrocarbon fractions are described in U. S. Patent 2,270,620 to Bray. The synthetic organic acids used in the preparation of oil-soluble metal saltsare preferably obtained by oxidizing relatively high molecular weight hydrocarbon fractions such as highly paraffinic lubricating oil fractions and the like or paraffin wax. The acids so produced may be converted into the metal salts directly or they may be chlorinated and the chlorinated acids converted into their metal salts. Preferably the acids will contain'in excess of 10 carbon atoms per molecule.

Suitable oil-soluble metal salts of acids produced by the reaction of a phosphorus sulfide or oxide with alcohol or with phenol are preferably those alkyl, aryl, or aralkyl phosphoric or thiophosphoric acid salts prepared by the reaction to P2S5 of P205 with an alcohol or phenol. The method of preparing theselsalts is fully described in the Freuler U. S. Patent 2,364,284. These reaction products may be described as the reaction products of a sulfide or oxide of phosphorus with a monohydroxy organic compound.

Metals which may be used to form the desired metal salts of the reaction products of phosphorus sulfides or oxides with sulfonic acids as well as the salts or soaps of each of the additive materials described hereinabove include the alkaline earth metals, calcium, strontium, barium and magnesium, and the polyvalent metals such as zinc, nickel, aluminum, lead, magnese, mercury, copper, iron, tin, chromium. bismuth and thorium. In some instances the alkali metal, i. e., the sodium, potassium or lithium, salts or soaps may be employed.

The products of this invention may be employed to improve the lubricating qualities of any lubricating oil, but I prefer to use mineral lubricating oils, especially mineral lubricating oils having a viscosity index (defined by Dean and Davis, Chemical and Metallurgical Engineering, vol. 36, page 618 (1929)) in the range of about 75 to about 95, such as those produced by solvent treating paraillnic base stocks. I v

In preparing high quality lubricating compositions I may add to a lubricating oil a sufficient quantity of the metal salts of the reaction product obtained by reacting phosphorus oxide or sulfur with a-sulfonic acid to impart to the finished lubricating oil a phosphorus content in the desired range. I' may also add the desired quantities of one or more of the lubricating oil additives described herein to the-above composition to impart other and additional specific and desirable properties to the finished composition. The metal salts employed are oil-soluble and require only simple mixing with a lubricating oil to obtain solution. However, the blending is usually effected at slightly elevated temperatures in the range of 100 F. to 200 F. in order to facilitate solution and dispersion of the addition agents in the body of the lubricating oil.

Methods which have been employed to evaluate lubricating compositions of my invention include various accelerated engine tests. These tests have been run on oils without the addition of my agents and on oils containing my addition agents.

Three difierent engine tests have been employed in the evaluation of my lubricating oils. These tests have been carried out in Lauson single cylinder engines, standard 6 cylinder Chevrolet engines and a single cylinder Caterpillar'Diesel standard test engine. The tests are referred to as the Lauson engine test, the Chevrolet engine test and the Caterpillar test, respectively.

In carrying out the Lauson engine test, the engine is operated for a total of 60 hours under a load of about 3.5 horsepower with a coolant temperature of about 295 F. and an oil temperature of about 280 F. This test is employed to determine the lacquering and corrosion tendencies of the oil. At the end of the test the cleanliness of. the engine is observed and given a numerical "detergency rating" between 0 and 100%, where 100% indicates a perfectly clean engine. Thusa detergency rating of 100 would indicate 10 that there were substantially no lacquer or varnish-like deposits within the engine. The corrosivity of the oil is measured by determining the loss in weight of corrosion sensitivity copperlead bearings after 20, 40 and 60 hours of operation. In some instances the corrosivity'is also determined by measuring the loss in weight of a lead strip suspended in the oil in the crank case of the engine. In those cases in which corrosion was extremely severe and there appeared danger of engine failure due to excessive corrosion of the copper-lead bearings as indicated by an examination made at the 20-hour or 40-hour period, these hearings were replaced witth babbitt bearings in order to complete the tes In the Chevrolet engine test the engine is operated under a load of about 30 horsepower with a coolant temperature of about 200 F. and an oil temperature of about 280 F. This test is used to evaluate corrosivity of the lubricant. The loss in weight of copper-lead bearings is determined after 8, 16, 24, 36, 44 and 52 hours of operation. I

In the Caterpillar test which is employed to determine the detergency of an oil, i. e., the ability of the oil to prevent lacquering of the engine, the engine is operated for a period of hours under a load of about 19.8 horsepower with a coolant temperature of about 175 F. and an oil temperature of about F. At the end of the test a numerical detergency rating" is assigned. The method of rating is similar. to that employed in the Lauson engine test and 100% indicates a completely clean engine.

The following specific examples are given to further illustrate my invention, however, they should not be taken as limiting the broad aspects of. my invention.

Example I .To 50 grams of petroleum sulfonic acids, prepared by treating a, sodium sulfonate concentrate comprising 60% by weight of oil-soluble sodium sulfonates and 40% by weight of mineral oil with an aqueous solution of sulfuric acid containing 50% by weight of H2804, were added 7.0 grams phosphorus pentasulfide, 350 ml. of a parafllnic solvent, having a boiling range of about 140 F.

to about 200 F. and consisting primarily of hexanes and heptanes, and 50 ml. of a paraflinic lubricating oil in the SAE 20 range. The mixture was heated at the reflux temperature, approximately F., for about 12 hours. A few grams of Ca(OH)2 were then added and the mixture heated and refluxed until neutral. The resulting mixture was filtered to remove unreacted Ca(OH)z and the filtrate topped to about 260 F. to remove the paramnic solvent. The evaporated product contained 2.25% sulfur and 0.5% phosphorus. This material will be designated hereinafter as product A.

The eflicacy of product A in preventing corrosion of alloy bearings of'the copper-lead type and in preventing oxidation of a lubricating oil resulting in the formation of acids was demonstrated in a laboratory oxidation and corrosion test. In this test the lubricating oil is maintained at a temperature of 270 F. in the presence of an alloy bearing of the copper-lead type while passing air through the oil at a rate of 10 ml.per minute. The lubricating oil is evaluated for corrosivity by determining the loss in weight of the hearing at intervals during the test and for oxi- 7 dation stability by determining the amount of I ll acids present in the test.

A lubricant was prepared by dissolving 3.1% p

by weight of product A in a mineral lubricating oil of SAE 20 grade having a gravity of 295 API, a viscosity of 307 SSU at 100 F., a VGC of 0.310 and a viscosity index of 90. This lubricant was tested in the laboratory oxidation and corrosion test described hereabove. The results are shown in the following table together with results obtained with the mineral oil without added agent.

To 1,000 grams of the hydrocarbon fraction described hereinabove as furfural raflinate was added 2 liters of a hydrocarbon naphtha fraction 7 having a boiling range of about 200 F. to about 300 F. and the resulting solution was stirred with 333 milliliters of 60% fuming sulfuric acid which wa added at such a. rate that the temperature was maintained below about 68 F. When all of the acid had been added, the reaction mixture was poured into about three liters of the naphtha fraction described hereabove and the mixture thoroughly agitated and then allowed to stand over night. The hydrocarbon layer was separated from the aqueous layer and the aqueous layer washed several times with portions of the naphtha, fraction to recoversubstantiall all of the oil-soluble sulfonic acids. The original hydrocarbon layer and the washings were combined, fuel gaspassed through the solution for a short time to remove sulfur dioxide, concentrated to about two and one-half liters by blowing fuel gas onto thesurface of the solution at room temperature and filtered through finely ground diatomaceous earth to remove solids or insoluble material.

The filtrate was then refluxed with 75 grams of powdered Pass at a temperature of about 220 F. for six and one-half hours. The reaction mixture was filtered through finely ground diatomaceous earth to remove any unreacted P285 and the filtrate refluxed for one hour in the presence of excess Ca(OH)z. The solution was then filtered through finely ground diatomaceous earth to remove unreacted Ca(OH)z. The naphtha was removed from the filtrate by topping to 375 F. The yield of evaporated product amounted to 785 grams of material having phosphorus, sulfur and calcium contents of 0.28%, 2.58% and 1.12% by weight, respectively. This material will be designated hereinafter as product B.

A solution having a phosphoru content of 0.043% by weight and comprising 15.3% by weight of product B and 84.7% by weight of a mineral lubricating oil of SAE 30 grade having a gravity of 29.1 API, a viscosity of 540 SSU at 100 F., a

VGC of 0.806 and a viscosity index of 90 was evaluated for its lubricating properties in the oil at intervals during the in the following table.

Lauson engine test. The results are presented Weight loss, Mgs.

Dctcr- Pb strip susucncy Cu-Pb bearpcndcrlm crankggi gfiz hours caseoil, hours o;1+15 .a% product A 11 30 41 4 394 Oil (w thout addition agents) Control 68 200 600 1 Cu-Pb bearing Example III A further quantity of my lubricating oil addition agent was prepared in a manner similar to that described in Example 11. This product, which-had phosphorus, sulfur and calcium contents of 0.39%, 2.54% and 1.15% by weight, respectively, will be designated hereinafter as product C.

A solution having a phosphorus content of 0.036% by weight comprising 9.3% by weight of product C and 90.7% by weight of the mineral lubricating oi1 described in Example 11 was evaluated as a lubricant in the Lauson and Chevrolet engine tests. In the Chevrolet engine test bearing weight losses of copper-lead bearings after 36 hours of operation were 79 milligrams and 122 milligrams respectively, on two different bearings. The bearing weight loss determined with the mineral oil containing no additive was 3,000 milligrams.

- The results of the Lauson engine test on the lubricating composition are shown in the following table:

l Cu Pb bearing replaced by babbitt hearing at 40 hours due to excessive corrosion.

Example I A further quantity of my lubricating oil addition agent was prepared in the manner described in Example II. This product which had phosphorus, sulfur and calcium contents of 0.52%, 2.68% and 1.18% by weight, respectively, will be designated hereinafter as product D.

A lubricant having a phosphorus content of 0.049% prepared by blending 9.5% by weight of product D with 90.5% by weight of the mineral lubricating oil described in Example II was evaluated in the Caterpillar test. This lubricant received a detergency rating in this test of 79% as compared to 50% for the mineral oil without additives.

Modifications of this invention which would occur to 'one skilled in the art are to be considered a part of the invention as defined in the following claims.

I claim:

1. A composition of-matter adapted for addition to lubricating oil consisting of an oil-soluble metal salt of the reaction product of a phosphorus compound of the class consisting of phosphorus sulfides and phosphorus oxides with a petroleum sulfonic acid, said reaction product being obtained by reacting said sulfonic acid with between about 3% and about 50% by weight of said phosphorus compound at temperatures between about 100 F. and 400 F.

2. A composition of matteraccording to claim 1 in which said phosphorus compound is phosphorus pentasulfide.

3. A composition of matter according to claim 1 in which said phosphorus compound is phosreacting between about 3% and about 50% by weight of phosphorus and sulfur with mahogany sulfonic acids at a temperature between about 100 F and 400 F.

7. A composition of matter adapted for addition to lubricating oil consisting of an oil-soluble metal salt of the reaction product of a phosphorus compound of the class consisting of phosphorus sulfides and phosphorus oxides with a petroleum sulfonic acid prepared by sulfonating a hydrocarbon fraction which contains not more than about 20% by volume of material having a viscosity gravity constant outside the range of about 0.82 to about 0.90, said reaction product being obtained by reacting said sulfonic acid with between about 3% and about 50% by weight of said phosphorus compound at temperatures between about 100 F. and 400 F.

8. A composition of matter adapted for addition to lubricating oil consisting of an oil-soluble metal salt of the reaction product of phosphorus pentasulfide with an oil-soluble petroleum sulfonic acid, said oil-soluble petroleum sulfonic acid being obtained by sulfonating a petroleum fraction in the lubricating oil range which contains not more than about 20% by volume of material having a viscosity gravity con-,

stant outside the range of about 0.82 to about 0.90, said reaction product being obtained by reacting said sulfonic acid with between about 3% and about by weight of said phosphorus compound at temperatures between about 100 F. and 400 F. i

9. A lubricating composition comprising a major proportion of mineral lubricating oil and a small amount of an oil-soluble metal salt of the reaction product of a phosphorus compound of the class consisting of phosphorus sulfides and phosphorus oxides with a sulfonic acid, said reaction product being obtained by reacting said sulfonic acid'with between about 3% and about 50% by weight of said phosphorus compound at temperatures between about 100 F. and 400 F.

10. A lubricating composition comprising a major proportion of mineral lubricating oil and a small amount, sufficient to impart a phosphorus content to said oil of between about 0.01% and about 0.5% by weight, of an oil-soluble metal salt of the reaction product of a phosphorus compound of the class consisting of phosphorus sultides and phosphorus oxides with a petroleum sulfonic acid, said reaction product being obtained by reacting said sulfonic acid with between about 3% and about 50% by weight of said phosphorus compound at temperatures between about F. and 400 F.

11. A lubricating composition according to claim 10 in which said phosphorus compound is phosphorus pentasulfide.

12. A lubricating composition comprising a major proportion of mineral lubricating oil and a small amount, suflicient to impart a phosphorus content to said mineral lubricating oil of between about 0.01% to about 0.5% by weight of an oilsoluble metal salt of the reaction product of a phosphorus compound of the class consisting of phosphorus sulfides and phosphorus oxides with a petroleum sulfonic acid, said petroleum sulfonic acid comprising oil-soluble petroleum sulfonic acids obtained by sulfonatin a petroleum fraction which contains not more than about 20% by volume of material having a viscosity gravity constant outside the range of about 0.82 to about 0.90, said reaction product being obtained by reacting said sulfonic acid with between about 3% and about 50% by weight of said phosphorus compound at temperatures between about 100? F. and 400 F.

13. A lubricating composition according to claim 12 containing also between about 0.1% and about 5.0% by weight of an oil-soluble metal petroleum sulfonate.

14. A lubricating composition according to claim 12 containing also-between about 0.5% and about 2.5% by weight of an oil-soluble phenate.

1-5. A lubricating composition according to claim 12 containing also between about 0.5% and about 2.5% by weight of an oil-soluble metal salt of synthetic organic acids prepared by oxidizing high molecular weight petroleum hydrocarbon fractions.

16. A lubricating composition according. to claim 14 containing also between about 0.1% and 5.0% ,of an oil-soluble metal salt of the reaction product of a phosphorus compound of the class of phosphorus sulfides and phosphorus oxides with a monohydroxy organic compound.

17. A lubricating composition comprising a major proportion of mineral lubricating oil and a small amount,.suflicient to impart a phosphorus content to said mineral lubricating oil of between about 0.01% and about 0.5% by weight of an oilsoluble metal salt of the reaction product of phosphorus pentasulfide with an .oil-soluble petroleum sulfonic acid obtained by sulfonating a petroleum fraction in the lubricating oil range containing not more than about 20% by volume of material having a viscosity gravity constant outside the range of about 0.82 to about 0.90, said reaction product being obtained by reacting said petroleum sulfonic acid with between about 3% and about 50% by weight of phosphorus pentasulfide at temperatures between about 100 F. and 400 F.

18. A lubricating composition according to claim 17 wherein said hydrocarbon fraction is an intermediate petroleum hydrocarbon fraction obtained by solvent fractionation of a lubricating oil distillate wherein the most highly paramnic hydrocarbons present in said distillate are separated from said petroleum hydrocarbon fraction as a. raifinate and wherein the most highly aromatic hydrocarbons present in said distillate are separated from said petroleum hydrocarbon fraction as a solvent extract.

19. A composition as set forth in claim 1 in which the oil soluble metal salt is a calcium salt.

20. A composition as set forth in claim 1 in which the oil soluble metal salt is a nickel salt.

21. A composition as set forth in claim 1 in which the oil soluble metal salt is a zinc salt.

22. A composition as set forth in claim 17 in which the oil soluble metal salt is an alkaline earth metal salt.

23. A composition as set forth in claim 17 in which the oil soluble metal salt is a calcium salt.

24. A composition as set forth in claim 17 in which the oil soluble metal salt is a nickel salt.

25. A composition as set forth in claim 17 in which the oil soluble metal salt is a zinc salt.

PAUL W. FISCHER.

16 REFERENCES CITED UNITED STATES PA'IENTS Number Name Date 1,982,903 Clemmensen Dec. 4, 1934 2,242,260 Prutton May 20, 1941 2,309,829 Davis Feb. 2, 1943 2,349,785 Faust May 23, 1944 2,350,959 Cook June 6, 1944 2.364.284

Freuler Dec. 5, 1944 

